Magnetic head for perpendicular magnetic recording system

Abstract

A disc drive is disclosed incorporating a non-magnetic slider, a thin film main pole on the leading face thereof and a C-shaped flux collector extending forward from that same face, with the lower portion of the C-shaped flux collector being positioned slightly above the recording surface. The main pole, when energized, disperses the magnetic flux vertically through the "hard" medium and then through the "soft" medium to be returned to and collected by the foot of the C-shaped flux collector. In a preferred embodiment, the corners of this lower or foot portion of the flux collector are not sharp, to prevent flux concentration at any of those corners. In this design, the energizing coil may be wound about either a yoke which connects the C-shaped flux collector to the non-magnetic slider or the back portion of the flux collector itself.

What is claimed is: 
     
       1. A perpendicular recording magnetic head comprising a slider supporting said head for positioning movement across one side of a recording medium, a main pole supported on an end face of said slider, and a flux collector comprising a C-shaped ferrite pole, one end of said collector being supported by said slider, the other end of said C-shaped pole being separated from said main pole by a recording gap to complete the magnetic circuit through the recording medium, said collector other end and said main pole each having a surface which faces said recording medium wherein the area of the surface of said collector other end is greater than the area of the main pole surface. 
     
     
       2. A perpendicular magnetic recording head as in claim 1 wherein said C-shaped pole includes a back portion and a relatively thicker foot portion slidable over the recording surface and defining an elongated flux collecting surface adjacent said recording gap to collect the flux passing through said magnetic material from said main pole. 
     
     
       3. A perpendicular recording magnetic head as in claim 2 wherein the foot portion of said flux collector has rounded corners to evenly distribute the collected flux. 
     
     
       4. A perpendicular recording magnetic head as in claim 3 including a yoke connecting said C-shaped pole to said slider. 
     
     
       5. A perpendicular recording magnetic head as in claim 4 including a coil for controlling the magnetic recording wound around the yoke. 
     
     
       6. A perpendicular recording magnetic head as in claim 4 including a coil for controlling the magnetic recording wound around the back portion of the C-shaped pole. 
     
     
       7. A perpendicular recording magnetic head as in claim 1 wherein the main pole comprises a thin film head layered on the surface of the slider. 
     
     
       8. A perpendicular magnetic recording head as in claim 7 wherein the main pole comprises a think, highly permeable layer to concentrate the magnetic flux, said flux collector comprising a relatively long plane surface parallel to the surface of said magnetic material to collect the flux. 
     
     
       9. A perpendicular recording magnetic head as in claim 7 wherein said thin film head includes a reduced width portion at the foot of the slider, the reduced width portion of the head concentrating the flux at a tip thereof to reduce the width of the recorded bit. 
     
     
       10. A perpendicular recording magnetic head as in claim 9, wherein the sides of the reduced width head portion are curved to concentrate the flux at the head portion nearest the surface of the magnetic recording medium. 
     
     
       11. A perpendicular recording magnetic system including a recording medium comprising a non-magnetic substrate, a soft magnetic layer over said substrate and a hard magnetic layer with a vertical orientation around said soft magnetic layer, a slider for positioning an access transducer over the recording medium comprising a ferrite access head including, a main pole disposed on a face of the slider, a claw-shaped flux collector separated from said main pole by a gap substantially greater than said main pole thickness, said flux collector being magnetically coupled to said main pole and carried on the face of the slider, said collector having two ends separated by an intermediate portion with one end of said collector which faces said recording medium having an enlarged cross-section compared to a parallel section of said intermediate portion of the collector, a magnetic data access circuit being completed by selective passage of magnetic flux through the main pole, the soft magnetic layer and back to the flux collector on the same side of the recording medium as the main pole. 
     
     
       12. A recording system as in claim 11 wherein a foot portion of said flux collector facing said main pole has rounded corners to evenly distribute the collected flux. 
     
     
       13. A recording system as in claim 12 including a yoke connecting said claw-shaped flux collector to said slider and a coil for controlling the magnetic recording wound around the yoke. 
     
     
       14. A recording system as in claim 13 wherein said thin film head includes a reduced width portion at a foot of the slider, the reduced width portion of the head concentrating the flux at a tip thereof to reduce the width of the recorded bit. 
     
     
       15. A recording system as in claim 14 wherein the main pole comprises a thin, highly permeable layer to concentrate the magnetic flux, and said flux collector has a relatively long surface parallel to said magnetic surface to collect said flux. 
     
     
       16. A recording system as in claim 15 wherein a gap between the flux collector and the main pole is about 400 microinches. 
     
     
       17. A system as in claim 15 wherein the gap between the flux collector and the main pole is substantially greater than the thickness of the main pole. 
     
     
       18. A magnetic recording system as in claim 11 including a back bar of magnetic material on a face of said slider, and attached to the main pole disposed on the face of the back bar to convey the magnetic flux to said main pole. 
     
     
       19. A magnetic recording system as in claim 18 including a notch on the bottom of said back bar terminating in said gap and filled with a non-magnetic material, whereby a concentrated magnetic field path is defined through said flux collector and said back bar. 
     
     
       20. A magnetic recording system as in claim 19 wherein said notch is defined on one side by an angled surface on a face of the back bar facing said main pole, said surface angling away from said main pole toward said slider. 
     
     
       21. A magnetic recording system as in claim 11 including a magnetic back bar disposed on the surface of said main pole for supplying the magnetic flux to the main pole, said flux collector being mounted on said back bar to complete the magnetic circuit. 
     
     
       22. A magnetic recording system as in claim 21 wherein said back bar includes an angled face on the bottom surface thereof, said angled face being directed toward the flux collector and extending from said main pole up away from the surface of said recording medium, thereby defining one face of said gap.